submerged coast

Ice ages tie up immense quantities of the planet’s water in continental glaciers, lowering the sea level precipitously. In interglacial periods like our own, the ice melts and raises the oceans by hundreds of feet, resulting in submerged coasts. Tops of hills become islands, and old valleys turn into bays or fjords. In the short moment of our industrial civilization, as we warm the climate by burning fossil fuels, scientists predict this inundation will continue, probably with catastrophic results for hundreds of millions of people living on flat ground near the ocean’s edge.

Bill McKibben